It is well known that topical skin surfaces of humans, from time to time, need to be cleaned and desirably, sanitized.
Currently, there are only two over-the-counter antimicrobial active ingredients enjoying unqualified approval by the U.S. Food and Drug Administration for use in antiseptic skin cleansing, for first aid and wound cleansing, and in antifungal cleansing wipes.
The first, ethyl alcohol, has a long history of safe and effective use. However, there is a long list of negative attributes associated with the use of the ethyl alcohol. It dries and irritates healthy skin and stings injured or abraded skin. Moreover, as ethyl alcohol is highly volatile, it dissipates rapidly if not packaged in a proper barrier container.
Other disadvantages of ethyl alcohol include its stringent regulation by governmental agencies, its ability to erode some metals, its tendency to remove paint and varnish and to delaminate some plastics.
The other approved antimicrobial ingredient is PVP-iodine (also called Povidone-iodine), which is a stable complex of polyvinylpyrrolidone (PVP) and elemental iodine. While elemental iodine has been used in antiseptic applications (U.S. Pat. No. 4,045,364), elemental iodine is known to possess a number of undesirable properties. Free elemental iodine is highly toxic, irritative, sensitizing, odorous and it also causes stains and readily vaporizes due to sublimation. U.S. Pat. No. 2,739,922 teaches the complex of PVP and iodine, which possesses reduced objectionable properties and increased bactericidal activity as compared to free elemental iodine. PVP-iodine has a variety of uses in health care on both skin and hard surfaces as an effective germicide, bactericide, fungicide, virucide, and amebicide.
The use of pre-moistened wipes to deliver aqueous solutions containing alcohol or PVP-iodine to sanitize skin or to disinfect hard surfaces is longstanding. But such wet wipes are expensive because they require barrier packaging to prevent evaporation or “dryout”. Also contributing to the expense of such wipes is the need for special binder-free substrates for hydro-alcoholic formulations and starch-free substrates for aqueous iodophor formulations. Thus, the use of these ingredients has been limited and reserved for higher risk healthcare and medical environments where other considerations justify the higher costs.
U.S. Pat. No. 2,599,140 discloses an iodine-containing detergent using iodine dissolved in a mixture of polyalkylene glycol and glycerin to prevent fast evaporation of elemental iodine. U.S. Pat. No. 4,355,021 discloses a substantially dry virucidal wipe using a flexible paper substrate, having iodine stabilized in polyoxyethylene (40) sorbitol septaoleate. U.S. Pat. No. 4,045,364 discloses dry disposable paper tissues impregnated with elemental iodine or PVP-iodine, which can be packaged and stored for long term without undue deterioration. U.S. Pat. No. 5,919,471 discloses a substantially flexible, dry and antiseptic wipe impregnated with PVP-iodine present in at least one glycol compound.